Airworthiness Directives; Stemme GmbH & Co. KG Models S10-V and S10-VT Sailplanes

This amendment adopts a new airworthiness directive (AD) that applies to Stemme GmbH & Co. KG (Stemme) Models S10-V and S10-VT sailplanes. This AD supersedes AD 98-15-24, which currently requires replacing the propeller blade suspension forks with parts of improved design on Stemme S10-V sailplanes. This AD requires you to remove the propeller blade suspension forks, exchange them with the manufacturer for improved design forks, and install the improved design propeller blade suspension forks. This AD is the result of analysis that shows that the existing propeller blade suspension forks are currently cracking more rapidly than originally projected. The actions specified by this AD are intended to prevent certain propeller blade suspension forks from cracking, which could result in the loss of a propeller blade during flight with possible lateral imbalance and loss of thrust.